I see high frequency data

In the previous post I shared an example how to get high frequency data from IB broker (well, it is retail version of HFD – it has only best bid/ask and the trades). Now, once you saved some data – what should you do next?

Next logical step would be data sanity check and visualization. For example, while preparing R script for this post, I found, that IB data contains numerous duplicates in the quotes. Every time, when the trade happens, IB trading platform sends the price and the size of the trade bundled together. Additionally, it sends the size of the trade as separate quote as well and this completely mess up the data. So, data sanity check and visualization gave me a hint, that something is wrong with the data.

Today I want to show an example in R, which loads data from mongodb and plots some parts of the data. This should give you better intuition on collected data.

The plot shows bid (light blue) prices , ask(green) prices and the trades (red). The size of the red dot indicates volume of the trade.